Can you use "where" to require an attribute in c#?

c# generics attributes constraints where
juan picture juan · Oct 21, 2008 · Viewed 7k times · Source

I want to make a generic class that accepts only serializable classes, can it be done with the where constraint?

The concept I'm looking for is this:

public class MyClass<T> where T : //[is serializable/has the serializable attribute]

Answer

Jon Skeet picture Jon Skeet · Oct 21, 2008

Nope, I'm afraid not. The only things you can do with constraints are:

  • where T : class - T must be a reference type
  • where T : struct - T must be a non-nullable value type
  • where T : SomeClass - T must be SomeClass or derive from it
  • where T : ISomeInterface - T must be ISomeInterface or implement it
  • where T : new() - T must have a public parameterless constructor

Various combinations are feasible, but not all. Nothing about attributes.

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